It is expected that information processing devices such as server devices, storage devices and network devices will explosively increase for the recent rapid development of information communication and toward an age of fusion of broadcasting and communication. On the other hand, in order to reduce carbon dioxide for the prevention of global warming, it is necessary to reduce the power consumption of information processing infrastructure including these information processing devices. In particular, in a data center taking a role of the information processing infrastructure in the back end, in addition to the device power which is the power consumed by a group of information processing devices, the cooling power which is the power consumed by cooling equipment for cooling the devices also accounts for a large share of the power consumption, and comprehensive power reduction of the device power and the cooling power is what needs to be achieved.
Respective approaches for the power saving of the data center have been started in information processing devices such as server devices, storage devices and network devices, cooling equipment, and operation management. In the information processing device, the improvement in performance per power consumption by means of a low-power device and the employment of the power saving function by the switching of operating states in accordance with workload have been promoted. In the cooling equipment, the operational efficiency improvement of an air conditioner itself, the optimization of an airflow design of an inlet and an outlet and the introduction of local cooling and liquid cooling have been started. In the operation management, the operation information monitoring, the job scheduling and the operational efficiency improvement or consolidation of a device group by means of virtualization have been adopted as main measures. Though the cooling equipment is generally designed based on the maximum rated power of the device group, the power consumption of the cooling equipment during operation depends heavily on distribution and fluctuation of the power of the device group with respect to the cooling equipment. For example, since the efficiency of the air conditioner depends on the power or heat generation of the device, a position relationship and a distance between the air conditioner and the device, a temperature, an air volume, an airflow direction and the like, the cooling power is heavily influenced by the power and the arrangement of the device. Since it is expected that consolidation of server devices by means of virtualization technology will be utilized for the power saving with the advance of an operation management technology of the data center, it becomes necessary to take measures to reduce the total power of the device group and the cooling equipment with due consideration of the uneven power distribution and the time fluctuation of the device group with respect to the cooling equipment. Some examples have been conventionally known as the operation management method of devices such as server devices and storage devices and cooling equipment, but they still remain in local or sequential measures in terms of the comprehensive power saving described above.
In Japanese Patent Application Laid-Open Publication No. 2004-126968 (Patent Document 1), in a management server for performing the job scheduling to parallel computers, a new job is input into a low-temperature computer based on temperature sensor information of the computers, and a job is transferred from a high-temperature computer to a low-temperature computer, thereby preventing the failure and the performance degradation in the parallel computers due to high temperature. Furthermore, whether to transfer a job is determined by estimating the power consumption of each computer and cooling equipment provided for each computer before and after the job transfer based on temperature information.
In Japanese Patent Application Laid-Open Publication No. 2007-179437 (Patent Document 2), in a management system for a plurality of computers, an overheated computer and a non-overheated computer are extracted based on temperature distribution and operation information of the computers, and software is transferred from the former to the latter, thereby achieving the power saving. Furthermore, after the extraction of target computers, fluctuations in computer power and air conditioner power before and after the transfer of the software are compared, thereby determining whether to transfer the software. The computer power is obtained from the operation information, the air conditioner power is obtained from the temperature distribution, and the temperature distribution is obtained from temperature sensors, a temperature history and the operation information.
In US Patent Application Publication No. 2006/0259621 (Patent Document 3), in a method of allocating workloads to a plurality of servers in a data center, a requested workload profile is compared with a historical profile, and the requested workload is allocated to a server in accordance with a history that minimizes the power of the server and an air conditioner, or randomly allocated if there is no matching history. The historical profile includes server location, class, operation information, inlet temperature, outlet temperature, workload type and power of the server and air conditioner. The power of the server and air conditioner is obtained from the inlet and outlet temperatures of the server, specific heat and air volume or measured by a power meter.
In US Patent Application Publication No. 2006/0259793 (Patent Document 4), in a method of distributing power to a plurality of servers in a data center, power budgets are lent and borrowed between the servers or racks that are close in geographic location so as to approach to an ideal and analog temperature distribution or power distribution, and a discretized power state of the server is assigned based on the budget distribution, thereby preventing the failure of the servers due to a hot spot or a cold spot. A thermal multiplier indicating ideal power for each server is obtained from an outlet temperature of each server, a reference outlet temperature of an average server and a supply air temperature of air conditioner.    Patent Document 1: Japanese Patent Application Laid-Open Publication No. 2004-126968    Patent Document 2: Japanese Patent Application Laid-Open Publication No. 2007-179437    Patent Document 3: US Patent Application Publication No. 2006/0259621    Patent Document 4: US Patent Application Publication No. 2006/0259793